At present, an electric vehicle is charged by visiting a charging station. However, because the number of the charging stations is limited, it is inconvenient to charge the electric vehicle, thus affecting a popularity of the electric vehicle.
Currently, the electric vehicle is charged either by an AC electricity of low power (such as, 3.3 KW, 7 KW, 30 KW) or a DC electricity of high power. However, the charging at a DC charging station has disadvantages of low efficiency, long charging time, high cost and large covering area, and thus it is very difficult to popularize the charging station. In addition, due to the limited space of the electric vehicle, the in-vehicle charger restricted by the volume thereof is unable to meet the requirement of high charging power.
Besides, a charging apparatus including a DC-DC module is currently used to charge the electric vehicle, which cannot meet the need of quick charging of the electric vehicle.